I'm looking for a web app which will allow me to create a 3D model of a cupboard I need to design for coursework. So that rules out floorplanner.
I can't install or execute an exe file on the school computers, so no sketchup, and the alternative is a web app. Are there any around?

Butterfly is a new and innovative
technology developed by the Autodesk
Israel team to bring the power of
AutoCAD, the world’s leading design
solution, to the Web for the first
time. Project Butterfly enables users
to view, edit, and share complex
designs and drawings using just a Web
browser.

Dubbed as ”Google Docs for AutoCAD.”
Project Butterfly is considered by
industry experts to be one the most
complex and technically advanced web
applications today.